ISO 19043:2015

INTERNATIONAL ISO
STANDARD 19043
First edition
2015-09-01
Natural rubber latex concentrate —
Determination of total phosphate
content by spectrophotometric method
Concentré de latex de caoutchouc naturel — Détermination de la
teneur totale en phosphate par méthode spectrophotométrique
Reference number
ISO 19043:2015(E)
©
ISO 2015

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ISO 19043:2015(E)

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ISO 19043:2015(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Principle . 1
4 Apparatus . 1
5 Reagents . 1
6 Procedure. 2
6.1 General . 2
6.2 Determination of total solids content . 2
6.3 Preparation of standard phosphate solutions . 2
6.4 Determination of phosphate content. 2
7 Expression of results . 3
8 Precision data . 3
9 Test report . 3
Annex A (informative) Precision data . 4
Bibliography . 6
© ISO 2015 – All rights reserved iii

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ISO 19043:2015(E)

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
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Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information
The committee responsible for this document is ISO/TC 45, Rubber and rubber products, Subcommittee
SC 3, Raw materials (including latex) for use in the rubber industry.
iv © ISO 2015 – All rights reserved

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INTERNATIONAL STANDARD ISO 19043:2015(E)
Natural rubber latex concentrate — Determination of total
phosphate content by spectrophotometric method
1 Scope
This International Standard specifies a method for the determination of total phosphate content of
natural rubber latex concentrate. This method is not necessarily suitable for latex from natural sources
other than the Hevea brasiliensis.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
ISO 124, Latex, rubber — Determination of total solids content
ISO 648, Laboratory glassware — Single-volume pipettes
3 Principle
Approximately 20 g of concentrated latex, of which the total solids content has been determined, is
coagulated with hydrochloric acid.
The coagulated latex is removed and the serum filtered through filter paper.
The residual phosphate present in a known volume of the serum is determined by measuring absorbance
with a spectrophotometer at wavelength 470 nm.
4 Apparatus
4.1 Balance, accurate to 0,1 mg.
3 3
4.2 Volumetric pipettes, of capacity 10 cm and 25 cm , complying with the requirements of
ISO 648, class A.
5 Reagents
Use reagents
...